An OTN (Optical transport network), as a core technology of a next generation transport network, is capable of implementing flexible scheduling and management of high-capacity services, and increasingly becomes a mainstream technology of a backbone transport network.
With the rapid development of data services, the current OTN system can no longer well satisfy the requirement of directly bearing multiple services with various rates. Aiming at the requirement, the ITU-T is discussing about formulating a new ODUflex frame to satisfy the requirement. The ODUflex frame may bear a packet service at any rate, and in this case, the ODUflex rate is opted to be n*1.24416 G, where 1≦n≦80. Since the ODUflex frame cannot directly pass a line interface, but needs to be encapsulated to an HO ODU (Higher Order Optical Channel Data Unit) and to be transported through the HO OTU (Higher Order Optical Channel Transport Unit). A current mapping manner of an ODUflex frame to an HO ODU uses the GMP (Generic Mapping Procedures), where the ODUflex occupies some time slots of the HO ODU.
A packet service traffic has a property of non-real time changing, so in different time periods, the ODUflex is required to provide various bandwidth to satisfy various packet service traffic, and is required not to affect the normal transmission of the packet service while ODUflex channel bandwidth is adjusted.
Therefore, how to achieve the lossless adjustment of ODUflex channel bandwidth has become a practical problem that is required to be solved while a packet service is borne through an ODUflex.